body,h2 {
    margin: 0;
}

html,body,#app,.app {
    height: 100%;
}

.flex {
    display: flex;
}

.app {
    flex-direction: column;
    position: relative;
}

.app-header {
    height: 60px;
    background-color:#2f44ff;
    text-align: center;
    line-height: 60px;
    position: relative;
    z-index: 9;
}

.app-header span {
    font-size: 22px;
    font-weight: bold;
}

.app-body {
    flex: 1;
    background-color: #f3f3f3;
}

.app-footer {
    height: 60px;
    background-color:  #CCCCCC;
}

.app-footer ul {
    margin: 0;
    padding: 0;
    list-style: none;
    height: 60px;
}

.app-footer ul li {
    flex: 1;
    text-align: center;
    flex-direction: column;
    display: flex;
    justify-content: center;
}

.active {
    color: red;
}


.app-footer ul li i {
    font-size: 25px;
}

.app-header a {
    color: inherit;
    text-decoration: none;
    -webkit-tap-highlight-color: transparent;
    position: absolute;
    left: 0;
}

.app-header a i {
    font-size: 16px;
}